In integrated circuit (IC) structures, a transistor is a critical component for implementing digital circuitry designs. Generally, a transistor includes three electrical terminals: a source, a drain, and a gate. By applying different voltages to the gate terminal, the flow of electric current between the source and the drain can be turned on and off. A gate structure, which may include conductive materials such as metals, can be formed over a semiconductor portion of the transistor structure to govern the operation of the transistor. By applying a voltage to the gate structure, an electrically conductive channel can be created between the source and drain terminals of the portion of semiconductor material positioned in contact with the gate.
Pitch is a quantity which measures the amount of separation between two features. A value of “pitch” specifies a sum of the width of a feature (e.g., a transistor gate) and the space on one side of the feature separating that feature from a neighboring feature. Depending on the photolithographic process being used, factors such as optics and wavelengths of light or radiation restrict how small the pitch can be before features can no longer be reliably printed to a wafer or mask. As such, the pitch limits the smallest size of any features that can be created on a wafer. Various changes and improvements to IC fabrication, over time, have accommodated progressive reductions in pitch to provide greater component densities and greater operational sophistication in an IC product. In some portions of an IC, however, the reduced pitch may be associated with unanticipated changes in electrical behavior such as shorting and/or general changes in threshold voltage, current, etc. Although techniques for selective fabrication to provide a larger pitch between elements are possible, their implementation can also introduce additional steps to otherwise streamlined processes of forming transistor elements at particular locations.